News (Updated November 20,
2005)
[Home]
[Previous
news]
LONDON (Reuters) - People infected with the HIV virus in Britain have one of the highest levels of drug resistance in the world, and the rate is increasing, researchers said on Friday.
The trend suggests a wave of infections from a drug resistant strain of the virus may be on the way, they said in a study published in the British Medical Journal.
The report by the UK Group on Transmitted HIV Drug Resistance warned that the reduction in effective drugs to treat patients represented "a major clinical and public health problem".
Their research was based on 2,357 HIV positive patients between 1996 and 2003.
They found that 335 patients showed some degree of resistance to one or more of the antiretroviral drugs used to fight the HIV virus, which can lead to AIDS.
Most, 257 of them, were resistant to drugs in one class only, 44 were resistant to drugs within two classes and 34 were resistant to drugs in the three most commonly used drug classes.
The study said this was equivalent to a 14 percent rate of resistance over the whole time period, rising to 19 percent for the most recent year of the study, 2002-3.
This is higher than in other industrialized countries.
Drug resistance is estimated at 7 percent among chronically infected HIV patients in the United States, with a 6 percent resistance in France and 10 percent elsewhere in Europe.
Friday November 18, 10:03 PM
Tests carried out in Yaounde showed that malaria, which kills a child in Africa every 30 seconds, boosts production of a substance that could increase HIV replication in the placenta and prevent it fully protecting the foetus from infections.
"Our research highlights the fact that placental malaria ... could play an important role in mother-to-child HIV transmission in utero that has been underestimated so far," said Anfumbom Kfutwah, a virologist at Cameroon's Pasteur Centre.
Researchers began investigating the links between malaria and HIV, which can lead to AIDS, after discovering that HIV transmission from mother to child increased at the end of the rainy season, when malaria is most prevalent.
"Each disease by itself is a major problem both for the individuals affected and the health care system," said Andreas Heddini from the Multilateral Initiative on Malaria, which is organising a pan-African malaria conference in Yaounde.
"But the fact that they frequently occur together is a major complicating factor and we need more research to clarify how the two infections interact and how to best treat co-infection," he said in a statement issued at the conference.
AIDS -- for which there is no known cure -- killed about 2.3 million people last year in Africa. An estimated 3.1 million were newly infected during the past year alone.
TWO BIGGEST HEALTH RISKS
An estimated 15 to 30 percent of mothers infected with HIV will transmit the infection during pregnancy and delivery in the absence of medical help, according to the World Health Organisation.
Kfutwah said the study, in collaboration with the Institut Pasteur research foundation in Paris, looked at placentas from women who were HIV positive and negative and who had malaria or were free of the disease.
Evidence of a link between malaria and foetal HIV infection could prompt health authorities to consider routinely testing pregnant women in African countries for both diseases, he said, while treating women for malaria during pregnancy could become a way to reduce the risks of HIV transmission.
"It's clear that African scientists are aware that we cannot look at HIV and malaria in isolation," Heddini said.
"We must investigate any interactions between what are arguably the two biggest health threats facing the continent."
Hopes for an effective malaria vaccine, which doctors consider the best hope in fighting the disease, were boosted on Tuesday by new research presented at the conference showing an experimental shot can protect children for at least 18 months.
Researchers said GlaxoSmithKline Plc's vaccine reduced cases of life-threatening malaria by 49 percent and all clinical cases by 35 percent in a group of Mozambican children treated in 2003.
Thu Nov 17, 2005 3:49 PM ET
By Paul Simao
ATLANTA (Reuters) - The rate of HIV diagnoses in the United States was stable between 2001 and 2004 but fell 5 percent per year among blacks, one of the groups hardest hit by the AIDS epidemic, federal health officials said on Thursday.
The Centers for Disease Control and Prevention, which released the data, said the drop in new reported HIV infections in the black community appeared to be tied to corresponding declines among intravenous drug users and heterosexuals.
Despite the good news, officials with the Atlanta-based federal agency said the battle lines of the AIDS war continued to be marked as much by race as sexual orientation and warned high-risk groups not to be complacent about the disease.
"We must work to accelerate successes among black women and to reduce the extremely high levels of infection among black men who have sex with men," said Dr. Ronald Valdiserri, acting director of the CDC's national center for prevention of HIV, sexually transmitted diseases and tuberculosis.
A total of 38,685 Americans were diagnosed with HIV in 2004, compared to 41,207 in 2001, according to the CDC study, which was based on data from 33 states that have confidential, name-based reporting of HIV and AIDS cases.
Blacks, who make up about 13 percent of the population, accounted for 51 percent of the 157,252 diagnoses in the period. Their rate of HIV diagnosis was 76.3 per 100,000 in 2004, down from 88.7 per 100,000 in 2001.
Blacks were 8.4 times more likely to be told they had the AIDS virus in 2004 than whites. The U.S. rate was 20.7 diagnoses per 100,000 in 2004, compared to 22.8 per 100,000 in 2001.
The CDC said the drop in the national rate was not statistically significant.
Despite the drop in diagnoses among blacks, the overall rate has stayed steady largely because of a higher number of gay and bisexual men testing positive for the disease.
Gay and bisexual men continued to be the group most impacted by HIV, accounting for 44 percent of the diagnoses between 2001 and 2004. There were 8 percent more diagnoses in this high-risk group between 2003 and 2004.
Intravenous drug users, who can get the virus from sharing dirty needles, made up 17 percent of the total diagnoses in the three-year period, while heterosexuals accounted for about 34 percent of the new reported infections.
There was a 9 percent average annual decline in diagnoses among intravenous drug users and about a 4 percent average annual drop for heterosexuals in the period, according to the CDC study.
Most of the intravenous drug users and heterosexuals who tested positive for AIDS were black.
The agency said providing high-risk groups with testing and prevention services was a key step to halting the spread of HIV. About one-quarter of those infected are believed to be unaware of their HIV status.
AIDS activists, however, attack the approach, which was introduced two years ago, because they believe it leads to reduced funding for programs that emphasize condom use and other safe-sex practices for uninfected people.
AIDS, which destroys the immune system and leaves people vulnerable to opportunistic infections and cancers, has killed about a half million Americans and at least 22 million people worldwide since 1981.
Health experts have been warning of a possible resurgence of the epidemic, which eased in the early 1990s following the development of antiretroviral drugs targeting the disease.
Tue Nov 15, 2005 3:34 PM GMT
By Amy Norton
NEW YORK (Reuters Health) - Nurse practitioners and physician assistants can care for HIV patients as well as doctors specializing in the disease -- and may do a better job than non-specialist doctors, researchers reported Monday.
Their study, of 68 HIV clinics in the U.S., found that nurse practitioners and physician assistants offered a quality of care similar to that of doctors specializing in HIV/AIDS. And they generally outperformed generalist doctors in the eight quality-of-care measures the researchers considered.
Nurse practitioners (NPs) and physician assistants (PAs) go through education and training that allows them to diagnose and treat patients; while many provide primary care services, some specialize in managing certain diseases, including HIV/AIDS.
NPs and PAs have long been an important part of HIV care, but "almost nothing" had been known about how well they perform in the role of lead caregiver, said Dr. Ira B. Wilson of Tufts-New England Medical Center in Boston, the lead author of the new study.
The findings, he told Reuters Health, show they are doing good job.
There are, though, some "preconditions" to receiving high-quality HIV care from an NP or PA, Wilson and his colleagues note in a report in the Annals of Internal Medicine.
Namely, practitioners should specialize in treating HIV, have a good deal of practical experience and have easy access to a doctor with expertise in HIV. About half of patients in the study who primarily saw an NP or PA also visited a doctor at some point during the year.
Wilson and his colleagues based their findings on medical records for 6,651 patients treated at 68 government-funded HIV clinics across the U.S. The researchers focused on eight indicators of quality of care -- such as the use of powerful HIV drug combinations known as HAART, and preventive services such as flu shots and screening for hepatitis C, tuberculosis and cervical cancer.
On most of these measures, the researchers found, NPs and PAs offered a quality of care similar to that of doctors specializing in HIV, and better than that of generalist doctors. On two quality measures, NPs and PAs even outperformed specialist physicians.
But Wilson cautioned against viewing the findings in terms of "who's better," particularly when it comes to a chronic, complex disease like HIV/AIDS, which is probably best managed by a team of healthcare providers.
"This is a message about training, expertise and teamwork," he said.
The fact that NPs and PAs can provide high-quality HIV care, Wilson noted, is especially relevant to rural and inner-city areas in the U.S., where there are often doctor shortages -- as well as to those developing nations hardest-hit by the AIDS epidemic.
SOURCE: Annals of Internal Medicine, November 15, 2005.
Mon Nov 14, 2:35 PM ET
South Africa's first phase II HIV vaccine trials intended to help battle an AIDS epidemic were launched by charitable group the International AIDS Vaccine Initiative (IAVI) and U.S.-based Targeted Genetics Corporation.
The trials will test the safety of tgAAC09, a vaccine candidate that is based on the HIV sub-type most prevalent in southern and eastern Africa, the two groups said in a joint statement on Monday.
Sub-Saharan Africa is the region hardest hit by AIDS, with more than 25 million people estimated to be infected with HIV, the virus that leads to the disease.
South Africa has the highest caseload of HIV in the world, with about one in nine of its 45 million population carrying the virus, while in neighbouring Botswana and Swaziland prevalence is as high as 40 percent.
"We are pleased that South Africa has taken a leading role in the testing of vaccine candidates given the medical and humanitarian promise a preventative vaccine holds," said Eftyhia Vardas, a doctor at the country's Perinatal HIV Research Unit, who will coordinate the trials.
Investigators test the immune response and acquire more data on safety during second phase trials on drugs that have already been proven safe during first phase tests.
The vaccine candidate, developed by U.S.-based Targeted Genetics, will be tested on 78 volunteers at three sites in South Africa. The trial is expected to last 18 months.
IAVI, a global non-profit organization working to accelerate the development of an AIDS vaccine, estimates that around 30 preventative HIV vaccine candidates are in human trials.
Friday November 18, 3:09 pm ET
Reyataz, also a protease inhibitor, is a substance that prevents white blood cells that have been infected with HIV from producing new copies of the virus.
The study of 419 HIV-positive patients taking protease inhibitors found that 7 percent of those who had their treatment switched to a Reyataz-based regimen had their virus levels go back up, compared with 16 percent of patients who continued with their respective protease inhibitor treatments. Patients switched to the Reyataz group outnumbered those that did not by 2-to-1 in the study.
The company did not identify other protease inhibitors used. Commercially available protease inhibitors include GlaxoSmithKline PLC's Agenerase and Lexiva, Boehringer Ingelheim's Aptivus, Merck & Co.'s Crixivan, Roche's Holding Ltd.'s Fortovase and Invirase, Abbott Laboratories' Kaletra and Norvir, and Pfizer Inc.'s Viracept.
Bristol-Myers Squibb shares rose 30 cents to $22.27 in afternoon trading on the New York Stock Exchange.
Friday November 18, 12:15 pm ET
The company used four different doses of MK-0518, a compound meant to block an enzyme needed for the HIV virus to enter a cell, as a standalone therapy in 35 patients over 10 days. The treatment lowered the virus levels in all patients by at least 98 percent in all doses, and half of the patients achieved a virus level of less than 400 copies per milliliter of blood. Patients enrolled had at least 5,000 copies of the virus per milliliter at the beginning of treatment.
Merck said it recently started a 48-week clinical trial testing MK-0518 against efavirenz, the active ingredient in Bristol-Myers Squibb Co.'s Sustiva, and plans to study the drug for a longer time in more patients.
Shares of Merck rose 49 cents to $30.10 in midday trading on the New York Stock Exchange.